Balk connector



Aug. 4, 1953 Filed Jan. 7, 1949 L. P. FROST BALK CONNECTOR 4 *She ets-Sheet 1 Patented Aug. 4, 1953 OF FlCE BALK CONNECTOR Lester P. Frost, Placerville, Calif. Application January 1, 1949, Serial No. 69,767

15 Claims. (01. 14-43) (Granted under Title 35,.U. S. Code sec. 266) 1 The invention described herein may be manufactured and used by 01' for the Government for governmental purposes, without payment to me of any royalty thereon. The present invention provides improved connecting means for connecting together adjacent ends of structural members in either fixed or floating bridges, such as balk beams or stringers, which carry the flooring of a bridge. Thus, timber placed lengthwise in a trestle or a floating bridge upon which the floor of the bridge is laid customarily is termed balk, and the present. invention provides means for rapidly and easily interconnecting adjacent ends of such timbers or stringers to form a full length floormounting structure; while the term balk is used in bridge construction to designate floor-supporting timbers the term as used in the present description is intended to have a broader scope or application than just to timbers, as the balk or stringer members may be made of steel, or any other suitable material of requisite strength, and all of such materials are indicated as being includable under the term balk.

As has been indicated above, the invention has for one of its objects the provision of balk-conheatin means for effecting rapid and expeditious interconnecting adjoining ends of balk to form a continuous floor-supporting structure of requisite length and strentgh. A further object of the invention is to provide means for connecting together adjacent ends of balk in such manner that a section of the bridge may be removed laterally out of the completed bridge without undue difficulties in order to replace a damaged section of the bridge.

A still further object of the invention is to provide connector means which are self-contained within the balk members.

- Astill further object of the invention is to provide balk members in which the abutting ends thereof are hingeably connected together either above or below the continuous horizontal plane of .the upper surfaces of the balk members.

Further objects of the invention will become apparent as the description proceeds, and the Fig. 2 is aperspective view of the assembly of Fig. 1, the view illustrating the opposite side of the assembly relative to the showing of Fig. 1;

Fig. 3 is a perspective view of the assembly of Fig. 1, but showing parts-0f the, connector in inactive position and the remaining parts of the connector serving as a hingejoint between the balk members;

Fig. 4 isa perspective view of the structure of Fig.1, but showing the parts-in disassembled relation; I

Fig. 5 is a perspective view similar to Fig. 4 but showing the parts in position for assembly; I

Fig. 6 is a side elevation of Fig. 1

Fig. 7 is a horizontal, fragmentary sectiona view taken on the line .VII-VII of Fig. 6, looking the direction of the arrows and showing details of the bottomlocking assembly;

Fi 8 is a fragmentary top plan view illustrating the details of the top locking instrumentaliies; 1

Fig. 9 is a horizontal sectional'view on the line IX-IX of Fig. 6, looking in thedirection of the arrows; i a i Fig. 10 is a sectional elevation taken on the line X-X of Fig. 6, looking in the direction of the arrows;

11 is a fragment ry side elevation of the adjoining ends of the balk members havingall of the locking means removed therefrom; I

Fig. 12 is a perspective view of a modified form ofconnecting means including the improved features of the invention; t Fig. 13 is a side elevation of the modification shown in Fig. 12, both of these views showing the locking means in locking position; Fig. 14 is a horizontal sectional view taken on the line XIV-XIV of Fig. 13; a k

Fig. 15 is a horizontal section taken on the line XV-XV of Fig. 13;

.Fig. 16 is a plan view, partially in section, of themodified form of connector; v v

Fig. 17is a vertical, sectional elevation taken on the line XVII-XVII of Fig. 13, looking in the direction of the arrows;v

Fig. 18 is .a fragmentary side elevation of the modified form of balk connector of Figs. 12 and 13, with the locking means removed; Fig. 19 is a plan view of a connecting link forming a part of the improved construction;

Fig. 20 is a side, elevation of the link of Fig. 19; Fig. 21 is-a side elevation of a stud shaft employed in the present construction; and

Fig. 22 is a side elevation of a tie bar and which extend inwardly and downwardly to lower horizontal end portions 48 and 48. A cut-out portion 49 is provided on the inner end of the upper horizontal flange 3 of thebalk member I adjacent to a cut-out portion" i, and'a cut-out portion 49' is provided on the inner end. or the horizontal portion 48' on the bottom flange 4. of the balk member 2 for a purpose which will hereinafter appear. The cut-tout portion I is formed in the adjoining end of the balk member I on theyupper horizontal flange 3- thereof. The balk n'ieinbers" hand 2 are-also provided with vertically-extending, parallel endportions and 5, rBSfle'ctively- The adjoining ends of the balk 'inembers I andf-are enlarged and provided with spaced verticallyextending, parallel side plates 6 and 6" respectively; whi'chside plates 6 and 6" diverge inwardly at their outer ends and abut against theveitieal end portions 5 and5' as illustrated Figs. '7 and 8. The adjoining ends of the balk members I and 2 are connected together by means'pf upper and lower tie bars 8 and 8' havingspaced 'parallel pins 9 and 9' respectively thereon. One-of the pins 9' of the upper tie bar 8 isadapted-to be inserted in an upper hole I0 formed in' the-side plates 6' of the balk member I and a'lso to pass through a hole II provided in one end of an upper connector-link l2; and the other pin-8 of' the tie bar 8 is adapted to be insertedin slightlyelongated holes l nein the side plates 6' of the balk member 2 and to pass through a slightly-elongated hole 48- substanti'ally in the middle of the upper. connector link I2. One of the pins 9' of the lower tie bar 8' is adapted to be inserted: in. slightly elongated holes I 0? imthe 1ower.:;portions ot'the side plates 6" of the balk member I and also to pass through a slightly. elongated: hole at substantially in the middle-of a lower connecting link- I2 and the other pin 9- onthe lower tie bar 8' is adapted to beinsertedinholes I0 in the lower portion of the balk member 2 and to pass throughv a hole I l in one end of the lower connecting link I2.

o er r not a s de p ate:- t of balk member I is mountedan operating handle l3 and on theupper portionrota side plate-6 of the balk member 2 ismounted an operating handle IS", with oneend of each of. the operathandles. I3 and I3 fitted on one end of each of' operator shafts or studs .HL and I4 respectively,. and held in place thereon by means of lockingpin's I5. One of each of the operator shafts I4 and I4 passesthrough one of each of the other 'e'nds' of'the connecting links I2 and I2, respectively; and are attachedthereto by locking pins I6, more particularly"illustratedin Fig. 9. lhe ti'e} bars 8 and-'8 and operating'handles l3 and I3 operate against wear members I! mounted on the-sides of the vertical side plates '6 and i of the balk members I and 2'. In order to prevent: the pins 9 and 9 of the upper and 'lbwertie'bars 8 and 8" from working out of their holes III and It, in theside plates 6 and 6, the free end's of the tie bar pins Sand 9 which ex- -tendithrougtsth'e opposite sides ot'the balkplates 4 6 and 6 are provided with locking clips I8, which are slipped into grooves I9 formed on the ends of the pins 9 and 9', as more particularly shown in Fig. 2.

Referring to Figs. 12 to 18, inclusive, the balk members 28 and 2!), which are of a modified form from those disclosed in Figs. 1' to- 1 1, inclusive,

consist of upper, horizontally-extending portions 2! and 2|, having a pair of spaced flanges 22 and 22, respectively, extending downwardly therefrom, and lower horizontally extending portions 23 and '23, with spaced flanges 24 and 24,

respectivelyextending upwardly therefrom. The

upper and lower horizontally extending portions 21 and 23" of the balk members and 20, respectively, are connected together by pairs of spaced vertically extending plates 25 and 25' which are beveled at their outer ends and the adjoining ends of the balk members are connected together by upper and lower tie bars 26 and 26", having pairs of spaced pins 21 and 21'" respectively provided thereon.

One of the pins 2 of the upper tie bar- 26 is adapted to be inserted in l iol'es 28 in the flanges of the balk member 25' and through a hole 4% in one end of an upper link M; and the other pin 2 1 oi the upper tie bar 26 is adapted to be inserted in slightly elongated holes 23' in the upper flanges 22- of the" balk member 20 and to extend through a slightly elongated hole 45- substantially in the middle of the link 44. One of the pins 2? of the lower tie bar 26' is" adapted to be inserted in holes 28" the lower flanges 2d of the ball: member 20 and to pass through a hole 2-3- in one end of the lower connector link to; and the other pin 27' of the lower tie bar 26 isadapted to be inserted in slightly elongated holes 28 in the lower flanges 24" of the balk member 28 and to pass through a slightly elongated opening 35 in the middle of the link 44'.

An operating handle 3| is fitted on one end of a shaft 32 extendin through openings BI formed in the downwardly extending. flanges 22 of the upper horizontally extending portion 21 of the balk member 20' and held in place thereon by pin 33. The shaft 32 also passes through a hole in the other end of the upper connecting link 44' where it is secured thereto by a pin 34.

Another operating handle 351s also fitted onzone end of a shaft 38 rotatably mounted on the upwardly extending flanges 24 of the lower hori- I Zontally extending portion 23* of. the balk member 20 and held in place thereon by pin 36-. The shaft 3 6 also passes through a hole 62 in: the other endof the lower connectin link 44",. and: is secured to the link in. any suitable manner. The

upper horizontal portion 2| of the balk member 20 is provided with cut-out portions 29 and 53 at its adjoining end; and. out-out portions 29' and 63" ar provided on the lower horizontal portion23 of the balk member 20 for a purpose which will. hereinafter. appear. To prevent the links 44 and M from being rotated; and held: in a locked. inoperative position, one of. the pins- 21 and: 21' of. the tie bars 26 and 28' may be inserted in holes 42 and 32 provided in the plates 25 and 25' of. the: balk members 29 and 20 respectively.

By providing the balk members I and 2 with one connector on each member including a connecting linkand operating handle,- thebalk members may be connected together readily end to end. For so connecting the balk members of Figs. 1 to 11 inclusive, the ends of the'balk memthe balk member I and the'other operating handle I3 is mounted onthe upper portion of the balk member 2. Upon operating the handles I3 and I3, the connector links I2 and'l2' are rotated with the link shafts I4 and I4" to a'horizontal position, while for locking the connecting links I2 and I2 in inoperative position, one of the pins 9 on the upper tie bar 8,isplaced in'holes 39 in side plates 6 of the balk member I and one of the pins 9 on the lower'tie bar 8' is placed in holes M in the side plates 6' of the balk member 2 with the other pin 9 of :theupper" tie bar 8 engaging in holes II] in the upper portions of the side plate 6 of the balk member I and the other pin 9 of the lower tie bar 8 engaging in holes I0" in the side plate 6' of the balk member 2. i I 1 In forming a continuous balk construction the pins 9 of the upper tie'bar 8 areremoved from their carrying position in holes III and 39 in the balk member I, and pins 9' of tie bar 8 are removed from their carrying position in holes I0" and M in the balk member 2, thereby permitting connecting links I2 and I2 to be rotated by handles I3 and I3, respectively, through shafts I4 and I 4'. Upon the operating handles I3 and I3 being turned until each connecting link I2 and I2 is in a horizontal position, the balk members I and 2 are shifted until a hole II in one end of the upper connector link I2, Fig. 6, is aligned with the holes I0 in the balk member I, and a hole II in one end of the lower connector link I2 is in alignment with lower holeslll" in the balk member 2. When these holes become in alignment, the pins 9 of the upper tie bar 8 are reinserted through the upper holes I0 and Illa, in the balk members I and 2, with the pin 9 of the upper tie bar 8, which is inserted in the holes I 0 of the balk member I, passing through the hole II in one end of the upper link I2; and the other pin 9 of the tie bar 8, which is inserted in the upper holes Inc in the balk member 2 passes through th elongated opening 40 in the 'middle of the upper link I2. The pins 9 of the lower tie bar 8' are also reinserted inthe lower holes I0, I0, of the balk members I and 2, with one of the pins 9' in the holes ID" of the balk member 2 passing through the hole II' in one end of the lower link I2, and the other pin 9' of the tie bar 8' in holes III of balk member I passing through the elongated hole 49 in the middle of the lower link I 2'. Lock clips I8 are then slipped over the free ends of the tie bar pins.

When the balk members I and'2 are so connected and used as a continuous beam structure, compression in the upper horizontalflanges 3 and 3' thereof and tension in thebottom flanges 4 and 4', are carried through the connector-locking shafts I4 and I4 into the connector links I2 and I2, through the pins 9 of the tie bar ,8 in the holes I0 in the upper portion of the balk member I, and through the pin 9' of the tie bar 8' in the holes ID" in the lower portion of the balk member 2. The pin 9 of upper tie bar, 8 which is placed through holes II] on the upper portion of the balk member I, and which also passes through the elongated hole 40 in the middle of the upper link I2, and the pin 9' of the lower tie rod 8' which is placed through hole I0 in the lower portion of the balk member I, and passes through the elongated middle hole 40' in the middle of the lower connecting link I2, are used only to take vertical shear throughthe balk joint and do not take any of the moment portion of side plate 6 of in a hole 42' ing the lower forma hinged l'forces: This'iszmade possible by the elongated holes 40 and 40' in the middlelof the upper and lower connector links I2 and I2 and the holes III on the upper portion of the balk member I and the lowerholes III and I0" in the lowersportions of the balk members, so that no stress is-pla'ced on-the tie-bars 8 and 8. v

In order to form a hinged joint construction for'use as an approach span to a bridge for river banks or trestles, either the upper tie bar 8 including its pins 9, or the lower tie bar 8'- including its pins 9', maybe removed fromthe balk members I and 2. If the balk members I- and 2 are to be hinged above the horizontal plane, one of the'pins 9* on the lower tie bar 8' may be inserted in the holes in the balk member 2 The lower connecting link I2 is then turned back into the balk member I between'theside plates 9 by the operating handle I3, leavingthe upper link I2 connected and the uppertie bar '8 and its pins 9 in place, as illustrated in Fig. 3.

The balk member I may be hinged'about a pin 9 of the upper tie bar's inserted in the upper holes I0 in the balk member I, with the cut-out portions 1 and 49 in the adjoining end of the upper horizontal portion 3 of the balk member I'permitting thismovement, Should it be desired to have the balk members I and'2 hinged-below the continuous horizontal'plane of the top surfaces of the members, one of the pins f the upper tie bar 8 may be inserted in the hole 39in the balk member I, or the tiebar 8, and-its-pins' 9'may be removed from the balk member I.- The upper connecting link I2 is then turned backintothe balk member 2 by the operating handle I3". This hinging of the balk members I and2 below the said horizontal plane is permitted by the open lower portions of the side plates 6 and the cutout portion 49 in the adjoining end inthe lower balk member2.

The modified form of balk members 26, 20 as illustrated in Figs. 12 to 18, inclusive, are provided with a connector embodying the some structural details and operating in the same manner as disclosed in Figs. 1, to ll inclusive, with the operating handle 3I being on the-upper portion of balk member 20, a'nd'thel operating handle 35 being on member 20.

the lower portion'jof the balk One of the pins 21 of the' upper tiebar 26 is adapted to engagein a'hole'42in the balk member 20 for holding the upper connecting link 44 in a locked 7 position; and a pin 21' on the lower tie bar 26' is adaptedtoengage in the balk member 20 for holdlink 44' in lockedpositionifTo 7 joint construction for use asan approach span to a bridge for river; banksor trestles, either the upper tie bar26 including its pins 21, or the lower tie bar 26' including' its pins 21', maybe removed from'the'balk members 20 and 20'. By removing the lowentie bar 2 6 and its pins 21 from the balk members 20 and 29', the balk members maybe hinged 'above the said horizontal plane, with the cut-outpertions 29 and '63 on the adjoining end of the upper portion of the balk member 20' permitting this movement; and to hinge the balk' members and 20 below the horizontal plane through the "top surfaces of the members, the lower tie bar 26' and its'pins 27' are reinserted in balkm'embers 20; and 20' and the upper'tie'bar26 and'its pins 21 removed from the balk members, with thelower'cut-out portions 29"and 53 on'fthe 7 adJoiningend of the balk membe'r'20' permitting this movement below the said horizontal plane.

assume Having thus described my invention, what- I chtims as-netvland wish to secure by Letters Patent is: I

- 1'1. A structural assembly for bridges, comprismg theoombination with a:- series of balk beanis connected end-to-e'ndrelation to form acontinuous balk structure, of connecting means-movably mounted on one end or one of the beams, a: recess in an adjacent end or an adjacent beam receiving the connecting means, a pivotal mounting for the connecting means secured to the'beam enabling the connecting means to be rotated between connecting and inactive positions, and loekinginstrumentalities removably mounted on thebeams and-extending between adjacent'beams and. having spaced parallelpins extending through; aligned apertures in adjacent ends of the adjacent beamsv and through the ends of the connecting means received therein, thereby releas ably locking the; beams together. e

2; A structural assembly for bridges, comprising the; combination with a plurality of beams oonnectedin series in end-to-end relation, of connecting means includinga connect-inglink metal-1y mounted on each end of the beams, whereby the links can be rotatedinto operative and-inoperative positions, the said links extending into a compiementalrecess inthe adjacent end-of arr-adjacent beam for receiving; an opposite connecting link, and removable tie-bars mounted on the beams and extending between adjacent beams, the said links having spaced-parallel lock,- ina pins extending into corresponding apertures .prb'vided therefor in the connecting links and adjacent beam ends to secure the connecting links and beams in connected; position.

3.. A structural assembly for bridges; comprising the combination with a plurality of beams connected together at adjacent ends, and having spaced-vertically" extending plates at their adjacent ends, of means for connecting together adjacent ends of the beams, the meansincluding links betweensaid plates on upper and-lower portioiis of the plates, one of each of the links being rotatabl y mounted on one of the adjacent ends,

ftie-bars extending between adjacent beams and provided with spaced parallel pins on upper and -loiw'erjportions'of the plates-,the said pins extendthrough aligned openings in said plates and fiiearison said tie-bar pins for holding on the plates, a shaft rotatably mounted in upperpartmns of said plates or one or the fbe'ams, and a second shaft rotatably mounted in rower portions orthe plates of.- another of said seams, one breach of the sha-its passing through 1 an opening in one end or eachor the connecting links and secured thereto,- and an operatinglever m sa-time mounted on one end of eachofi said shafts for? rotating the links by means of the shafts upon the removal of said tiebars and-pins ffo'fii-th ends oft'he beams.

41 A structural assembly for bridges comprising insemination wan a; pl rality (s eam; com netted together at adjacent ends, of spaced vertideny extending plates on the beans; and means for connecting adjacent eraser the beams;- the connect ng me ns including" links mounted between the plates at upper" and; lower positions thereof, pivotal mount gs forthe links, the said filfvfilial filoilhtl'fi'gs XtYidlhg through holes Ii IO- vidd therefore in the piates wiiefeby the conneeting' links be" rotated into operative and as er-savep'ositiohs' upper and lower tie-bars extending between adjacent beams and housing ispac'ed parallel locking pins extending through aligned apertures in the: plates and links for rigidly securing the beams together, means on the tie-bar pins for holding them on the plates, ashaft rotatabiy mounted-Oman upper portion of the plates or one or the beams, asecond shaft rotatabi-y mounted on lowerportions of the plates of the adjacent beam, one of each of the passing through an opening provided therefor in one end or the connecting links, and a handle mounted on one endofeaeh of the shafts for rotating the links by means of the shorts upon the removal; of the, tie-bars and pins from the ends of the beams.

5. A struotura-l? assembly for bridges comprising balk beams connected in end-to-end relation, means for connecting adjoining ends of the balk beams together, said means including a connecting linkfrotatably mounted on each of said ends, removable tie-bars having spaced pins thereon mounted on; the supportingmembers between said ends,- the tie-bar pins extending; through openings the ends; with one of each of the ofeach ofthe tie-bars passing through an e-longatedcpening the middle of one of each-of the said: links, and another of the of each or the tie-bars passingthrough an openingin one end of one of each of said links, shafts rotatably mounted on said ends of the supporting n ie1nbers-,; one of each of said shafts passing through anopening in one of each ofthe other ends of saidli n-ks and-secured thereto,, and an operatinghandle mounted on each of said shafts for rotating the links; through the shafts upon the remoyal of saidtie-bars and pins from said ends oi the supporting members.

6. structural assembly for bridges comprising balk membersconnected inendeto endrelation, the said balk members comprising spaced vertically extending plates on the ends ofthebal-k members opened at their lower portions, lower flanges and horizontal upper portions on the balk members cut-out portions on an upper horizontal portion of one of saidbalk members at its adjoining end and a cut-out; portion on the lower portion of anotherof; said-balk members, the said assembly unconnected balk members comprising' connecting meansiirterconnecti-ngcontiguousends of the balk-rifim-bersfihe means includmg a plurality of connecting links extending beon, one of the tie bars and pins therefor being renovate niouhtedonthe upper portions of the plates beth'een the ends of adjoining balk memhers; and another or the tie-bars and pins being renovatit'moufited on the lower portions of the pirates-Eaten the ends of adjoining balk mem- 15ers, astray upon the removal of the lower tie bar and pins, the adjoining ends of the balk mense heroine connected for moving said balk-members relatively upwardly above the horizontal plane; of the longitudinai axis of the balk; member, the cut-out portion onthe adjoiningendof the upper horizontal portion of one or thebalkmembers permitting this movement, the saidtie barand-pins removed-from the lower portionsbf the plates may be reinserted in the said ends, and the saidupper tie bar and pins in carrying position may be removed from the :plane, a shaft rotatably mountedon the upper portion of the plates of one of said balk members, and a second shaft rotatablyv mounted on the lower portion of the plates of another of said balk members, one of each of said shaftsextending through one end ofeach of said links and secured thereto and operating handles mounted on the said shafts for rotating the links through the said shafts upon the removal of said tie bars and pins from said adjoining ends of the balk members. i 7. A structural assembly for bridges comprising balk beams connected in end-to-end relation, the balk beams having horizontally extending upper and lower flanges, the upper flanges being provided with spaced downwardly extending side flanges and said lower portions 1 being provided with spaced upwardly extending side flanges, the said balk beams of the structural assembly comprising spaced vertically ex-. tending plates between the horizontally extending upper and lower flanges and the side flanges,

an upper connecting link rotatably mounted on one of the balk beams and extending between the adjoining ends of the balk beams, a lower con necting link rotatably mounted on another of the balk beams and extending between the adjoining ends, upper and lower tiebars having of each of the links and secured thereto, and

'operating means mounted on one end of the shafts for rotating the links through theshafts upon removal of the tie-bars and pins from the supporting members.

provided with recesses complemental to thesaid linksforreceiving the links when the latter are in. extended position, operating shafts carrying the said links and mounted in the housings, and operating leverssecured to the shafts for turning the said shafts for rotatably actuating the said links. I 10. A balk assembly for a bridge structure com- .prising balk beams adapted to be interconnected in end-to-end alignment, the said balk beams comprising an end housingon each end of each of the balk beams, pivotally mounted connecting links housed in thesaid end housings-when in inoperative position, the connecting links of successive beams being oppositely vertically spaced and extendin in-opposite directions when projected in connecting; position, adjacent ends of '40 8. A structural beam adapted to be interconnected with similar beams in end-to-end alignment to form a continuous structural beam assembly, which comprises an end housing on each end of the beam,'connectinglinks pivoted in each' housing and enclosed therein when in inoperative position and extending outwardly from the housing when projected in connecting position, the said beam having top and bottom flanges extending in parallelism longitudinally of the beam, one of the flanges having an end recess adapted to receive a connecting link of :a contiguous beam of the assembly, operating shafts carrying the said links and mounted in and extending through the housings, operating levers secured to the shafts for turning the said shafts for actuating the said links, tie bars mounted on the beam and adapted to extend across the juncture between contiguous beams when assembled, and spaced parallel locking pins carried by the tie bars adapted to be received in corresponding holes provided therefor in the connecting links of the beam and in corresponding holes in the housing in alignment with the holes in the connecting links.

9. A balk assembly for a bridge structure, comprising balk beams adapted to be interconnected in end-to-end alignment, the said balk beams comprising an end housing on each end of the balk beams, rotatably mounted connecting links pivoted in the said end housings and enclosed therein when in inoperative position, the connecting links of successive beams being opposite- 1y vertically spaced and extending outwardly from the housings when projected in connecting position, adjacent ends of adjacent beams being the successive beams being provided with recesses complemental to the said links for receiving the links when the latter are in extended position, operating shafts for actuating the=links, operating levers mounted on the shafts forrotating the shafts to actuate the links, the; said connecting links and complemental end recesses beingso arrangedas to enable either end of one of the balk beams to be connected to either end of the succeeding balk beam, tie bars'interconnecting the'adjacent ends of successive beams, andlocking pins on the tie bars entering, openings provided therefor, in an end housingof ;one

beam and the corresponding connecting link of the successive beam. is

11. A-structural assembly for,.bridges, comprising the combination witha plurality of beams connected in series in end-,to-end relation,

of connecting means for the beams including connecting link means rotatably mounted in each of the beams'and movable between inoperative position housed in the ends of each beamand operative position extended from 'thesaidends, each end of the beams being provided' with a complemental recess receiving corresponding .opposite connecting-link means, and tie bars re- .movablymounted on the beams and provided with similarly extending locking pins projecting into the connecting link -means and adjacent beam for securing the said connecting link means and adjacent beams inconnected position.

12. A structuralgunit comprisingv a beam includin top and bottomflanges, a web intercom necting thev flanges and endporti'ons adapted to -.;receive and to interconnect withicorresponding end portions of similar beams in end -to-end relation to form a continuous structural assembly, each of the said end portions including a pair of side plates having portions thereof integral with the web and having other portions extending beyond the Web to form a channeled end housing on the beam, the said housing being provided with a plurality of spaced holes or apertures, a link pivotally mounted in the housing, a pivot shaft for the link extending through the housing, lever means on the shaft for turning the shaft and link between a retracted inoperative position enclosed in the housing and operative connecting position projecting from the housing. the said link being provided with holes registering with selected holes in the housing, and a tie bar removably mounted on the housing provided with spaced locking pins removably received in selected holes in a side plate of the housing for removably retaining the tie bar in a retracted position on the side plate intermediate the said lever and the end of the beam, the said tie bar being shiftable from the said position into another position with an end of the tie bar projecting beyond the housing and the end of the beam hile releasing the lever -for enabling the latter t he ti rneu for extending the link from provided with a plurality of spaced holes or apertures, -a *link'pivotall-y mounted in the housing, a pivot shaft for the link extending through the "housing, lever means on the shaft for turning the shaft and link between a retracted inoperative position enclosed in the housing and operative connecting position projecting from the housing, the said linkbeing provided with holes registering with selected holes in the housing, and a tie bar removably mounted on the housing provided with spaced locking pins removably received in selected holes in a'sidc plate of the housing for removably retaining the tie bar in a retracted position on the side plateand intermediate the said lever on the link shaft and the end of the beam and restraining the said lever when the lever is turned to retract the link into the housing, the said tie bar being shiftable responsively to removal of the looking pins f-rom the holes into a position with an end of the tie bar projectingbeyond the'en'd of the beam while releasing the lever for enabling the latter to be turned for projecting the on; from the housing.

- -14. A structural unit for a bridge comprising a beam including top and bottom flanges, a web interconnecting the flanges and enlarged offset end portions adapted to receive and to interconnect with corresponding end portions of similar beams in .end-to-end relation to form a continuous structural assembly, each of the said end portions including a pair of side plates having portions thereof integral with the web and having other portions extending beyond the web to form a channeled end housing on the beam, the said housing being providedwith a plurality of spaced holes or apertures, a link pivotally mounted in the housing adjacent to one of the flanges of the beam, a pivot shaft for the link extending through the housing, lever means on the shaft tor turning the shaft and link between a retracted inoperative position enclosed in the housing and operative connecting position .projecting from the housing, the said link being provided with holes therethrough registering with selected holes in the housing, and a tie bar mounted on the housing providing with spaced "locking pins removably received in selected holes in the housing and retained thereby for holding the tie bar substantially parallel with the end of the beam and in advance of the lever means when the link is in retracted position enclosed in the housing.

15. A beam-like member having a web and opposite end portions adapted to receive and to ,connect thereto corresponding end portions of similar beams to form a structural unit, the said end portions comprising a pair of side plates having a portion rigidly secured to the web, remaining portions of the-side plates extending beyond the web and defining a channel therewith,

the said side plates having a plurality of spaced holes therein, a link in the channel, moans extending through a first set of the holes for pivotally mounting the link in the channel, means extending through a second set of holes and the link for locking the link to the channel, the second set of holes being in longitudinally spaced relation to the first set, a third set of holes being in vertically spaced relation to the second set of holes, a tie bar removably mounted "in the third set of holes and "having a pair of spaced locking pins reinovably received in the third set of holes, the pivoted link in one of the end portions of the beam being adjacent to the lower edge of the web and a similar pivoted link in theopposite end portion of the beam is adjacent to the top edge of the web.

LESTER P. FROST.

References Qited in the file of this patent UNITED STATES PATENTS Number Name Date 320,679 Martin June 16, 1885 1,448,854 Martin Mar. 20, 1923 1,467,696 Stewart Sept. 11, 1923 1,887,252 Thomas Nov. 8, 1932 1,941,348 Hathorn Dec. 26, 1933 2,171,326 Tarbet Aug. 29, 1939 2,291,014 Woody July 28, 1942 

